1. Field of the Invention
The present invention relates to information recording carriers which are utilized in the information technology referred to as RFID (Radio Frequency Identification). Specifically, the present invention relates to semiconductor devices capable of inputting and outputting information by electromagnetic waves. Moreover, the present invention relates to semiconductor devices such as noncontact type IC tags or inlets (also referred to as inlays and inserts) incorporated in such noncontact type IC tags.
2. Description of the Related Art
Information technology which is referred to as RFID (Radio Frequency Identification) has been spreading. For example, an IC tag is known, which is a tag having an outside dimension of several centimeters, storing data and communicating with a reader wirelessly. An IC tag includes an antenna and an IC chip having a communication circuit and a memory.
One mode of an IC tag is known, in which an IC tag is embedded in paper (for example, Reference 1: Japanese Published Patent Application No. 2002-049901, and Reference 2: Japanese Published Patent Application No. 2004-102353). According to Reference 1, in order to embed an IC tag having a thickness of less than or equal to 200 μm in an object such as paper, a metal layer for forming an antenna is formed to be thinner in a region in which an IC chip is mounted than the other regions. According to Reference 2, a semiconductor chip formed by sectioning a semiconductor wafer is connected to an antenna and is sealed by resin, thereby thinning an IC tag.